Cadillac 2007 CTS Owner's Manual page 95

Battery Replacement
Under normal use, the battery in the RKE
transmitter should last about four years.
The battery is weak if the transmitter will not work
at the normal range in any location. If you have
to get close to your vehicle before the transmitter
works, it is probably time to change the battery.
Notice: When replacing the battery, use
care not to touch any of the circuitry. Static
from your body transferred to these surfaces
may damage the transmitter.
1. Use a flat thin object to pry open the
transmitter.
2. Remove the old battery, but do not use a
metal object.
3. Insert the new battery as the instructions
under the cover indicate.
4. Snap the front and the back of the transmitter
together. Make sure the cover is on tightly, so
water will not get in.
5. Press any button on the RKE transmitter to
resynchronize the transmitter.
6. Test the operation of the transmitter with the
vehicle.
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